1. Field of the Invention
The present invention relates to an image processing apparatus, a computer program product, and a preview image displaying method.
2. Description of the Related Art
In recent years, image forming apparatuses have been commonly used, such as scanners that scan original images, copiers that print the original images scanned by the scanners, printers and facsimile machines that print image data input from the outside, and multifunction products (MFPs) that have functions of these apparatuses.
Such image forming apparatuses provide various functions, and allow a user to specify various settings as to the functions. The settings includes those concerning an original such as type and density of the original, those concerning image processing such as zoom ratio, simplex/duplex printing, and a margin size, and those concerning finishing such as stamping, stapling, and punching.
However, in the conventional image forming apparatuses, when a user sets such a finish function and starts printing, the user cannot check a finished state until a print result is obtained. For example, even if punch holes overlap an image in a finished state, it is not until the image is actually printed that the user notices this, which results in a waste of sheets.
To solve such a problem, Japanese Patent Application Laid-Open No. 2001-67347 discloses a conventional image forming apparatus that can display, prior to printing, a preview image of a finish result obtained by applying image processing with various functions to a pre-scanned original image to allow a user to change print settings when necessary.
The applicant has proposed, in Japanese Patent Application Laid-Open No. 2006-003568, an intuitive and highly convenient user interface. With the conventional user interface, when a user touches a specific position in a preview image of an original, a menu related to the position is displayed to allow the user to select a desired function for printing. Setting of a function selected by the user is immediately reflected in the preview image. With the user interface, unlike the case where a user select a function using a button on which a function name or an icon is written, it is possible to directly designate a position to which a user desires to apply a function and immediately check effect of the function. Thus, it is possible to perform operation intuitively, easily, and reliably.
However, there are problems yet to be solved, and the above conventional technologies still has a room for improvement.
In the conventional image forming apparatus, there is a limit in a direction in which an original is set. Positions where punching and stapling are applicable are limited to a few positions (mainly on the left side and the upper side) on condition that the original is set in a correct direction. Such specifications are set because, when setting of punching and stapling is allowed while the setting direction of the original is not correct, if expected finishing is not achieved, it is unclear what is the cause (mis-setting of the original or a setting mistake). Therefore, it is attempted to prevent the disorder by setting the original in the correct direction and prohibiting the setting of punching and stapling on the right side and the lower side, where the punching and the stapling are theoretically possible but are almost unnecessary practically.
On the other hand, with the conventional user interface, even if an original is not set in the correct direction, the direction of the original can be checked on the preview image. Thus, it is possible to rotate an original image when necessary or perform setting operation while the image is oriented in a wrong direction.
An image processing apparatus such as MFP is mounted with a “finisher” for punching and stapling. The finisher is disabled to punch and staple some positions depending on a direction of a sheet and setting details because of limitation on a structure thereof. Punching and stapling are impossible in the following cases:
(A) Stapling and punching in two positions set on sides parallel to a sheet direction (a paper feeding direction) selected
(B) Stapling/punching set on a different side than a side where punching/stapling has already been set
In other words, upon setting of stapling and punching, the problems described above occur in the following cases:
(1) When a sheet in a specific direction is designated, stapling and punching are set in positions where stapling and punching are not available
(2) After setting of stapling and punching, the sheet type is changed to the one on which stapling and punching are not available
(3) After setting of one of stapling and punching, another one of the functions is set in a position where the function is not available because of a positional relation between stapling and punching
Thus, in the conventional user interface, measures described as an example below are adopted. In the case of (1), when a sheet is selected, depression of a setting button is disabled for positions where punching and stapling are not available with the sheet selected. In the case of (2), a warning message is output and setting of finishing is neglected. In the case of (3), when one of punching and stapling is set, depression of a setting button is disabled for positions where the other function is not available.
However, in the specifications described above, it is difficult for a user to learn a reason why the setting is impossible. Thus, it is likely that the user repeats a similar mistake.